| 摘要 |
PURPOSE:To improve the strength of a bulb near the sealing section and reduce its damage when an end plate and the bulb are sealed by glass frit in a groove provided on the surface of the end plate by forming the cross-sectional shape of the bulb so as to intersect with a curve that follows the top of glass frit. CONSTITUTION:The vicinity 11 of the opening end 2 of a bulb 1 is molded into a curved shape with a smooth and continuous cross-sectional shape. This section is fit in a bulb receiving groove 7 and is sealed on an end plate 3 by glass frit 8. As a result, since the cross-sectional shape in the vicinity 11 of the sealing section of the bulb 1 is formed so as to intersect with a curve that follows the top of glass frit, the pulling stress applied to this section is diffused along the section 11 of a curve without being locally applied to th vicinity of a contact 10 between the surface of the bulb 1 and that of glass frit 8. As a result, the strength of the bulb 1 near the sealing section is improved sharply. |
